CVEs / CVE-2026-123158
CVE-2026-123158: OpenBSD OpenSSH vulnerability
- high 8.1 CVSS 3.1 (from the CNA)
- Last changed at its sources
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Description
sshd in OpenSSH before 10.6p2 on Linux, when musl libc is used without PAM, lacks a workaround for a password authentication bypass (related to misinterpretation of whether a string is intended to be a password hash). For some configurations of accounts, any password between 256 and 1024 characters succeeds. An example of a platform using musl libc without PAM is Alpine Linux.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| OpenBSD OpenSSH | before 10.6p2 | 10.6p2 |
Exploitation
Not in the CISA Known Exploited Vulnerabilities catalog as of 6 Nov 2026.
Severity
| CVSS 3.1 | 8.1 highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:HScored by the CNA ([email protected]) |
|---|---|
| Weakness | CWE-394 |
On the Stackurity blog
References
- CVE-2026-123158 on NVD
- CVE-2026-123158 on OSV
- https://github.com/leonjza/sshhole-lab Exploit, Third Party Advisory
- https://github.com/openssh/openssh-portable/commit/4353fdc43ef646c43a8dda7025cc1a898caf1482 Patch
- https://github.com/predkambrij/sshhole-repro Exploit, Third Party Advisory
- https://hachyderm.io/@damienmiller/117563026759098135 Third Party Advisory
- https://marc.info/?l=openssh-unix-dev&m=179388064263131&w=2 Mailing List, Vendor Advisory
- https://news.ycombinator.com/item?id=50377976 Issue Tracking
- https://news.ycombinator.com/item?id=50378228 Issue Tracking
- https://www.openssh.org/releasenotes.html#10.6p2 Release Notes
- http://www.openwall.com/lists/oss-security/2026/11/09/27
- https://alpinelinux.org/posts/2026-11-05-openssh-password-authentication-bypass/ Third Party Advisory
- https://github.com/coollabsio/coolify/discussions/12484 Third Party Advisory
- https://github.com/google/goonami-scanner/pull/277 Third Party Advisory
- https://github.com/panubo/docker-sshd/issues/93 Third Party Advisory
- https://news.ycombinator.com/item?id=50379704 Issue Tracking
- https://isc.sans.edu/diary.html?storyid=33498 Not Applicable
- https://sshhole.com Third Party Advisory
- https://sshole.events.greynoise.io/ Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-123158 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.